1. Field of the Invention
This invention relates to a pair of pipe cutting pincers, particularly to one used for cutting off plastic pipe.
2. Description of the Prior Art
A pair of conventional pipe cutting pincers, as shown in FIG. 1, includes a first long shell-shaped handle 1 and a second long shell-shaped handle 2 pivotally assembled at one side of the first handle 1. The first handle 1 has its front end pivotally installed with a blade 3 having its front side formed with a cutting edge 4, letting the front end of the pipe cutting pincers formed with a pincers mouth 5. The blade 3 has its rear end bent and extended toward a location between the first handle 1 and the second handle 2 and the circumferential edge of its rear end formed with saw teeth 6, and a crank 7 has one end secured at the rear end of the blade 3 and the other end fixed on the second handle 2. The second handle 2 is provided with a push key 8 at a location corresponding to the saw teeth 6 of the blade 3, and a torsion spring 9 is disposed on one side of the push key 8 for pushing and resisting the push key 8 to be able to elastically recover its original position. During cutting off a pipe, such as a plastic pipe or a water pipe, firstly, the second handle 2 is pressed to drive the push key 8 to push the saw teeth 6 and actuate the blade 3 to gradually move downward and close the pincers mouth 5. Next, adjust the cutting edge 4 of the blade 3 to clamp the pipe and then apply an axial force upon both the first and the second handle 1, 2 to enable the cutting edge 4 to diametrically cut off the pipe. To cut off a small-diameter pipe, as shown in FIG. 2, the push key 8 is adjusted and moved to the lower end of the toothed member 6 to let the pincers mouth 5 become comparatively small. During cutting the pipe, the second handle 2 is pressed to actuate the push key 8 to push against the saw teeth 6 at its upper end and as a result, the push key 8 will be disengaged from the blade 3, rendering the pipe cutting pincers unable to keep on cutting the pipe. At this time, the pipe is half cut and hence the first handle 1 and the second handle 2 must be stretched outward again to let the push key 8 resist against the toothed member 6 once more, and then the second handle 2 is continuously pressed to drive the push key 8 to push the saw teeth 6, and meanwhile the cutting edge 4 is adjusted to clamp the pipe for carrying out cutting. The conventional pipe cutting pincers are complicated in structure and assembly, and necessary to take a lot of exertion in operation.